U.S. patent number 4,668,402 [Application Number 06/677,831] was granted by the patent office on 1987-05-26 for system for treating fluids.
This patent grant is currently assigned to Culligan International Company. Invention is credited to William W. Norton.
United States Patent |
4,668,402 |
Norton |
May 26, 1987 |
System for treating fluids
Abstract
A process and system are provided for treating fluid. In one
illustrative embodiment, the treatment comprises the recharging of
a resin bed in a water softener. A flow switch and accumulating
timer are actuated when a selected flow rate is detected. The
accumulating timer is set to a selected elapsed time. A
chronological timer is also provided and is set for a selected time
of day to recharge the resin bed. A reserve brine capacity is
provided by delivering a selected amount of water to a brine tank
at predetermined elapsed time intervals of the accumulating timer.
The resin bed is recharged when both a selected elapsed time of the
accumulating timer has occurred and it is the selected time of
day.
Inventors: |
Norton; William W.
(Lincolnshire, IL) |
Assignee: |
Culligan International Company
(Northbrook, IL)
|
Family
ID: |
24720281 |
Appl.
No.: |
06/677,831 |
Filed: |
December 3, 1984 |
Current U.S.
Class: |
210/662; 210/105;
210/108; 210/140; 210/670; 210/793; 210/98 |
Current CPC
Class: |
B01J
49/80 (20170101); C02F 1/42 (20130101) |
Current International
Class: |
B01J
49/00 (20060101); C02F 1/42 (20060101); B01J
049/00 () |
Field of
Search: |
;210/662,670,687,739,89,98,102,103,108,109,140,143,190,191,269,275,791-798,105
;364/140,500,502 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Cintins; Ivars
Attorney, Agent or Firm: Gerstman; George H.
Claims
What is claimed is:
1. In a process for treating fluid with a water softening material
or a filtering material, a process for rejuvenating the water
softening material or the filtering material in the absence of a
flow meter, including the steps of:
providing a flow switch which will be actuated only when a selected
flow rate of the fluid is detected;
providing a first timer;
coupling the flow switch to the first timer to actuate the first
timer only when the flow switch is actuated;
determining the elapsed time of the first timer whereby a volume
flow measurement is simulated; and
rejuvenating the water softening material or the filtering material
in response to a signal generated by the first timer when a
selected elapsed time has occurred, whereby the use of a flow meter
is obviated.
2. A process as described in claim 1, including the step of
deactuating the first timer when the flow rate is less than the
selected flow rate and the flow switch is deactuated.
3. A process as described in claim 1, including the steps of
providing a chronological timer;
determining whether it is a selected time of day to rejuvenate the
water softening material or the filtering material;
rejuvenating the water softening material or the filtering material
when both the selected elapsed time has occurred and it is the
selected time of day to rejuvenate the water softening material or
the filtering material.
4. A process as described in claim 1, wherein said first timer
comprises one of a clock and a digital counter.
5. A process as described in claim 1, including the steps of
providing a set point timer;
determining whether a selected set point has been reached; and
if the set point has been reached, then determining the elapsed
time of the first timer and rejuvenating the water softening
material or the filtering material in proportion to the elapsed
time of the first timer divided by said selected elapsed time.
6. A process as described in claim 1, including the steps of
providing a chronological timer;
determining whether it is a selected time of day to treat the
fluid;
if it is the selected time of day to treat the fluid, then
determining the elapsed time of the first timer and rejuvenating
the water softening material or the filtering material in
proportion to the elapsed time of the first timer divided by the
selected elapsed time.
7. A process as described in claim 1, including the steps of
providing a set point timer;
determining whether a selected set point has been reached; and
if the set point has been reached, then determining the elapsed
time of the first timer and rejuvenating the water softening
material or the filtering material in proportion to the elapsed
time of the first timer divided by said selected elapsed time.
8. A process as described in claim 7, including the step of
deactuating the first timer when the flow rate is less than the
selected flow rate and the flow switch is deactuated.
9. A process as described in claim 1, wherein said rejuvenation
comprises the recharging of a resin bed in a water softener.
10. A process as described in claim 1, wherein said rejuvenation
comprises backwashing a filter in a water purification system.
11. A process as described in claim 1, wherein said rejuvenation
comprises adjusting the concentration of brine in a water softener
system.
12. A process as described in claim 1, including the steps of
providing a chronological timer;
determining whether it is a selected time of day to rejuvenate the
water softening material or the filtering material;
rejuvenating the water softening material or the filtering material
if either the selected elapsed time has occurred or it is the
selected time of day to rejuvenate the water softening material or
the filtering material.
13. A process for recharging a resin bed in a water system in the
absence of a flow meter, including the steps of:
providing a flow switch which will be actuated when a selected flow
rate is detected;
providing a first timer;
setting the first timer to a selected elapsed time;
coupling the flow switch to the first timer to actuate the first
timer only when the flow switch is actuated;
providing a chronological timer;
delivering a selected amount of water to a brine tank at
predetermined elapsed time intervals of said first timer;
determining from the chronological timer whether it is a selected
time of day to recharge the resin bed;
determining the elapsed time of the first timer whereby a volume
flow measurement is simulated; and
recharging the resin bed in response to signals from said first
timer and said chronological timer when both a selected elapsed
time has occurred and it is said selected time of day.
14. In a system for treating fluid with a water softening material
or a filtering material, apparatus for rejuvenating the water
softening material or the filtering material in the absence of a
flow meter, which comprises:
a flow switch adapted for actuation only when a selected flow rate
is detected;
a first timer adapted to be set to a selected elapsed time;
means coupling the flow switch to the first timer to actuate the
first timer only when the flow switch is actuated;
means for determining the elapsed time of the first timer whereby a
volume flow measurement is simulated; and
means for rejuvenating the water softening material or the
filtering material in response to a signal generated by the first
timer when a selected elapsed time has occurred, whereby the use of
a flow meter is obviated.
15. A system as described in claim 14, including means for
deactuating the first timer when the flow rate is less than the
selected flow rate.
16. A system as described in claim 14, including a chronological
timer;
means for determining whether it is the selected time of day to
rejuvenate the water softening material or the filtering material;
and
means for rejuvenating the water softening material or the
filtering material when both the selected elapsed time has occurred
and it is said selected time of day to rejuvenate the water
softening material or the filtering material.
17. A system as described in claim 14, wherein said first timer
comprises one of a clock and a digital counter.
18. A system as described in claim 14, including a set point timer
adapted to be set to a selected set point;
means for determining whether the selected set point has been
reached; and
means operable in response to the reaching of the set point for
rejuvenating the water softening material or the filtering material
in proportion to the elapsed time of the first timer divided by
said selected elapsed time.
19. A system as described in claim 14, including a chronological
timer adapted to be set to a selected treatment time of day;
means for determining when said selected treatment time of day has
occurred; and
means operable in response to the occurrence of said selected
treatment time of day for rejuvenating the water softening material
or the filtering material in proportion to the elapsed time of the
first timer divided by said selected elapsed time.
20. A system as described in claim 19, including a set point timer
adapted to be set to a selected set point;
means for determining whether the selected set point has been
reached; and
means operable in response to the reaching of the set point for
rejuvenating the water softening material or the filtering material
in proportion to the elapsed time of the first timer divided by
said selected elapsed time.
21. A system as described in claim 14, wherein said rejuvenation
comprises the recharging of a resin bed in a water softener.
22. A system as described in claim 14, wherein said rejuvenation
comprises backwashing a filter in a water purification system.
23. A system as described in claim 14, wherein said rejuvenation
comprises adjusting the concentration of brine in a water softener
system.
24. A system for recharging a resin bed in a water softener in the
absence of a flow meter, comprising:
an adjustable flow switch adapted for actuation only when a
selected flow rate is detected;
a first timer adapted to be set to a selected elapsed time;
means coupling the flow switch to the first timer to actuate the
first timer only when the flow switch is actuated;
a chronological timer;
means for determining when it is a selected time of day to
recharge;
means for determining the elapsed time of the first timer whereby a
volume flow measurement is simulated; and
means for recharging in response to signals from said first timer
and said chronological timer when both the selected elapsed time
has occurred and it is said selected time of day to treat the
fluid.
25. A system for recharging the resin bed in a water softener in
the absence of a flow meter, comprising:
an adjustable flow switch for actuation only when a selected flow
rate is detected;
a first timer adapted to be set to a selected elapsed time;
means coupling the flow switch to the first timer to actuate the
first timer only when the flow switch is actuated;
a chronological timer;
means for delivering a selected amount of water to a brine tank at
predetermined elapsed time intervals of said first timer;
means for determining from said chronological timer whether it is
the selected time of day to recharge the resin bed;
means for determining the elapsed time of the first timer whereby a
volume flow measurement is simulated; and
means for recharging the resin bed in response to signals from said
first timer and said chronological timer when both the selected
elapsed time has occurred and it is the selected time of day.
26. A process for recharging a resin bed in a water softening
system in the absence of a flow meter, including the steps of:
providing a flow switch which is actuated only when a selected flow
rate is detected;
providing a first timer;
coupling the flow switch to the first timer to actuate the first
timer only when the flow switch is actuated;
providing a chronological timer;
determining from the chronological timer whether it is a selected
time of day to recharge the resin bed;
determining the elapsed time of the first timer whereby a volume
flow measurement is simulated;
if both a selected elapsed time has occurred and it is said
selected time of day, then providing an amount of brine in
proportion to the actual elapsed time divided by the maximum
capacity elapsed time; and
recharging the resin bed.
27. In a process for treating fluid with a water softening
material, a process for rejuvenating the water softening material
in the absence of a flow meter, including the steps of:
providing a flow switch which will be actuated only when a selected
flow rate of the fluid is detected;
providing a first timer;
setting the first timer to a selected elapsed time;
coupling the flow switch to the first timer to actuate the first
timer only when the flow switch is actuated;
providing a chronological timer;
providing a predetermined capacity of treatment media at
predetermined elapsed time intervals of said first timer;
determining from said chronological timer whether it is a selected
time of day to rejuvenate the water softening material;
determining the elapsed time of the first timer whereby a volume
flow measurement is simulated; and
rejuvenating the water softening material in response to signals
generated by the first timer and the chronological timer when both
said selected elapsed time has occurred and it is said selected
time of day.
Description
BACKGROUND OF THE INVENTION
The present invention concerns a novel process and system for
treating fluid. Although the illustrative embodiments of the
invention primarily concern the recharging of a resin bed in a
water softener, the present invention is also applicable to fluid
treatment including the backwashing of a filter in a water
purification system, the removal of selected constituents from
water, the adjustment of the concentration of brine in a water
softener system, and other fluid treatments which will become
apparent from the description.
There are presently several methods of determining when recharging
of the resin bed in a water softener is required. In one method,
the electrical resistance of the resin bed is determined. The
resistance of the resin bed forms one arm of a resistive bridge,
and once a selected resistance is determined, recharging is
required. Another system for determining whether recharging is
required is by using a flow meter. The flow meter is used to
determine the amount of water that has been used. Once a selected
volume of water has been used as indicated by the flow meter, the
system is recharged. However, a flow meter is relatively expensive
and needs certain supporting hardware. In addition, certain flow
meters are subject to failure as a result of iron and/or turbidity
fouling the impellers of the flow meter. The turbine blade is
generally formed of plastic material with numerous vanes, and the
iron in the water may plate the vanes, eventually forming an
obstruction to proper rotation of the turbine.
Another method of determining when recharging should occur is
simply to recharge the resin bed every few days. This method can be
very wasteful, however, and on the other hand can be too infrequent
for various households.
In addition to determining when recharging should occur, when water
softeners are concerned one must consider the condition of the
brine tank. It is preferable for the brine tank to contain the
proper amount of saturated brine solution at the time of
recharging. The recharging comprises bathing the resin in brine to
remove hardness impurities and then rinsing the resin free of
excess brine. Thus, during service the raw water flows into the
softener tank, through the tank and out of the tank through a flow
switch to the household. The brine tank, which is coupled to the
system, is isolated during service. During recharging, the softener
tank is backwashed by directing the inlet water to the bottom of
the tank through a manifold and then backwashing the ion exchange
resin with the water flowing upwardly and out of the softener tank
to drain. Brine is then directed from the brine tank to the
softener tank, to the manifold and through the softener tank and
then to drain. The rinsing step comprises directing the inlet water
into the softener tank in the usual manner and washing out the
brine to rinse out the tank, although instead of directing the flow
from the outlet line to the household, the rinse water flows to
drain.
It can be seen that when a water softener is recharged, brine is
drawn up from the brine tank into the resin bed of the water
softener. After the recharging process is completed, more brine has
to be made. It is important that a sufficient saturated brine
solution be available at the next recharging time.
I have discovered a novel process and system for recharging the
resin in a water softener and my process and system are also useful
for other water treatments. In utilizing my invention, there is no
need to determine the electrical resistance of the resin bed, nor
is the use of a flow meter required in most embodiments of my
invention. Further, the problems concomitant with simply recharging
a resin bed every few days are alleviated by my process and system.
By using my novel fluid treatment process and system, the fluid may
be treated when required, at a selected time of day if desired, at
a selected day or days of the week, as desired, and in a water
softener system a proper volume of saturated brine solution will be
available at the time of recharging the resin bed.
SUMMARY OF THE INVENTION
In accordance with the present invention, a process is provided for
treating fluid. The process includes the steps of providing a flow
switch; adjusting the flow switch to be actuated when a selected
flow rate is detected; providing a first timer; coupling the flow
switch to the first timer to actuate the first timer when the flow
switch is actuated; determining the elapsed time of the first
timer; and treating the fluid when a selected elapsed time has
occurred.
In the illustrative embodiment, the first timer is deactuated when
the flow rate is less than the selected flow rate and the flow
switch is deactuated. A chronological timer is also provided. A
determination is made from the chronological timer whether it is a
selected time of day to treat the fluid. If both the elapsed time
has occurred and it is also the selected time of day to treat the
fluid, the fluid is treated.
In the illustrative embodiment, a set point timer is also provided.
A determination is made whether a selected set point has been
reached. If the set point has been reached, the elapsed time of the
first timer is determined. The fluid is treated in proportion to
the elapsed time of the first timer divided by the selected elapsed
time.
In another embodiment of the present invention, a process is
provided for recharging a resin bed in a water system. The process
includes the steps of providing a flow switch; adjusting the flow
switch to be actuated when a selected flow rate is detected;
providing a first timer; setting the first timer to a selected
elapsed time; coupling the flow switch to the first timer to
actuate the first timer when the flow switch is actuated; providing
a chronological timer; delivering a selected amount of water to a
brine tank at predetermined elapsed time intervals of the first
timer; determining from the chronological timer whether it is a
selected time of day to recharge the resin bed; determining the
elapsed time of the first timer; and recharging the resin bed when
both a selected elapsed time has occurred and it is the selected
time of day.
A more detailed explanation of the invention is provided in the
following description and claims, and is illustrated in the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a fluid treatment system in accordance
with the principles of the present invention;
FIG. 2 is a block diagram of a water softener recharging system in
accordance with the principles of the present invention;
FIG. 3 is a flow chart of a fluid treatment process in accordance
with one embodiment, based upon demand or maximum interval;
FIG. 4 is a flow chart of a fluid treatment process according to
another embodiment, based upon demand or time of day;
FIG. 5 is a flow chart of a fluid treatment process, in accordance
with another embodiment, responsive to demand or maximum interval
plus time of day;
FIG. 6 is a flow chart of a water softener recharging process in
accordance with another embodiment, responsive to demand and time
of day;
FIG. 7 is a flow chart of a water softener recharging process in
accordance with another embodiment in which a flow meter is used,
responsive to demand and time of day;
FIG. 8 is a flow chart of a water softener recharging process in
accordance with another embodiment, response to demand and time of
day and enabling proportional brining; and
FIG. 9 is a flow chart of a water softener recharging process in
accordance with a further embodiment in which a flow meter is used,
responsive to demand and time of day and enabling proportional
brining.
DETAIL DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS
Referring to FIG. 1, a fluid treatment system is shown therein in
which a flow switch 10 is coupled to the outlet line, for example,
from a water softener, a filter in a water purification system, or
any other outlet line from a device that has to be treated by
adding or removing chemicals, backwashing, removing constituents,
adjusting certain parameters, etc. Thus the present invention is
applicable to any fluid system in which there is a need to recharge
or rejuvenate or adjust or remove once a certain volume of fluid
flow has occurred.
Flow switch 10 is coupled to a first timer 12 which is a volume
flow timer operating to accumulate time once it is actuated by flow
switch 10. Volume flow timer 12 is coupled to a processor 14, which
may be a microprocessor in a microprocessor-based system or may be
another electrical or electromechanical or mechanical device if
appropriate.
Flow switch 10 is adjustable so that it is adapted to be adjusted
for actuation once a selected flow rate is detected. Thus once the
selected flow rate is detected, flow switch 10 will become actuated
to actuate volume flow timer 12.
A volume set switch 16 is coupled to processor 14. This sets the
volume that will be accumulated when the treatment is necessary.
However, instead of using a volumetric flow meter, volume flow
timer 12 is calibrated to approximate volume accumulated. For
example, if the system of FIG. 1 is used for recharging a water
softener, flow switch 10 may be adjusted for actuation when there
is a flow rate of two gallons per minute (gpm) or more. In this
manner, volume flow timer 12 will become operative to accumulate
time once flow switch 10 is actuated. By adjusting volume set 16,
the volume flow timer will be set to a selected elapsed time. For
example, if the volume is set to 2,000 gallons of water, processor
14 will operate volume flow timer 12 so as to set volume flow timer
12 to a selected time of 1,000 minutes. Once 1,000 minutes has been
accumulated by volume flow timer 12, a signal will be transmitted
to processor 14 to recharge the resin bed of the softener. It has
been found that the use of a volume flow timer provides an
approximate volume usage determination, without requiring the use
of a flow meter having turbine blades and the problems concomitant
therewith.
A hardness set switch 18 is also coupled to processor 14 in order
for the operator to set the desired hardness of the water to be
softened. Also coupled to processor 14 is a set point set switch 20
and a set point timer 22. The set point timer provides a maximum
time period between recharging of the resin bed. For example, if it
is desired to recharge the resin bed at least once every 24 hours,
whether there is sufficient volume demand or not, the set point set
switch 20 is operated to set the set point timer to 24 hours or
1,440 minutes. After each recharging cycle, the processor will
determine whether 1,440 minutes have elapsed without the volume
flow timer reaching the selected time and, if the 1,440 minute set
point has been reached, the resin bed will be recharged.
However, it is usually desirable that the water softener be
recharged only during periods of non-use. To this end, a
chronological timer 24 is provided. There is coupled to the
chronological timer a time of day set switch 26, which may be set
for a time of minimum water usage, such as 2:00 a.m. Also connected
to chronological timer 24 is a preset regeneration cycle circuit
28, for presetting a recharging cycle, for example, for every three
days. Thus with chronological timer 24 set for 2:00 a.m. and preset
regeneration cycle circuit 28 set for a three-day setting,
processor 14 will be signaled to recharge the resin bed at 2:00
a.m. every three days.
The chronological timer 24 and processor 14 is coupled to a display
30 for displaying data such as present time, the predetermined time
that is set for recharging, the preset recharging cycle period,
volume setting, hardness setting, set point setting, etc.
The demand system including the flow switch 10, volume flow timer
12 and volume set switch 16 may be combined with the maximum
interval system including the set point set switch 20 and the set
point timer 22, and may also be combined with the time of day
system including the time of day set switch 26, chronological timer
24 and preset regeneration cycle circuit 28. As can be more readily
understood from the flow charts described below, the demand,
maximum interval and time of day systems may operate independently
or in conjunction with each other.
Referring to FIG. 2, a water softener system is shown therein
comprising a softener tank 40 containing a bed of ion exchange
resin, a hard water inlet 42, a brine inlet 44, a water outlet 46,
and a drain 48. A brine tank 50 is coupled to the brine inlet 44 of
tank 40. Brine tank 50 includes a saturated brine solution that is
controlled in accordance with brine controller 52. Brine controller
50 is operative to adjust the concentration of brine delivered to
softener tank 40 or to deliver a certain amount or amounts of water
to the brine tank at predetermined intervals. The system is
controlled in response to approximated volume usage of water
flowing via line 46. The approximated volume is determined in the
aforesaid manner in which a flow switch, which is actuated when a
selected flow rate is detected, operates an accumulating timer. In
FIG. 2, flow switch 54 is connected in line 46 and provides an
analog signal in response to flow in line 46. The signal is
transmitted via line 56 to an analog to digital converter 58 from
where it is transmitted via line 60 to an input/output port 62 of a
microprocessor 64. Flow switch 54 may be a digital flow switch, not
requiring analog to digital converter 58. An appropriate program
for microprocessor 54 is contained within ROM 56. Hardness and
volume set switches 68 are coupled to microprocessor 64 and timer
setting 70 are also coupled to microprocessor 64. Microprocessor 64
operates with RAM 72 and is powered by household power 74 which is
connected to an AC to DC converter 76. The microprocessor provides
indicia of operating parameters on display 78.
The output of the microprocessor from input/outpot port 80 is
transmitted via line 82 to a digital to analog converter 84 for
feeding an analog signal via line 86 to brine controller 52. In a
specific example, the microprocessor includes a digital counter
which is operable to begin counting once flow switch 54 senses a
flow that is greater than two gpm. The flow signal is provided on
line 56, translated to a digital signal which is provided to the
microprocessor at input/output port 62. Once microprocessor 64
senses that a flow of greater than two gpm has been provided, the
digital counter will increment. However, when the flow is sensed to
be less than two gpm the digital counter will cease counting. The
digital counter has been set by volume setting switch 68 so that
once a certain count is reached, a signal will be presented via
line 82 to provide an analog signal on line 86 for operating brine
controller 52. The analog signal is responsive to the hardness
setting fed to the microprocessor from switch 68. Timer setting
switch 70 is operative to program the microprocessor so that even
though demand for recharging has been completed because the digital
counter has reached a selected count for recharging, recharging
will not occur until it is a certain time of day, for example, 2:00
a.m. Further, the timer setting switch 70 may be used to program
the microprocessor so that in addition to a chronological and
demand function, it also has a set point function whereby after a
predetermined time from a previous recharging, another recharging
will occur. For example, the timer setting switch 70 may be set so
that recharging will occur every 24 hours, whether there is
recharging demand or not.
In FIG. 3 a flow chart is presented showing a treatment mode in
which treatment occurs on demand or maximum interval. Referring to
FIG. 3, the hardness level and volume setting is made, and the set
point timer is set. The process commences and the set point timer
is started. A determination is made whether the water flow is
greater than a selected amount, which in FIG. 3 is A gpm. If it is
determined that the flow is greater than A gpm, the volumetric flow
timer starts. During operation of the volumetric flow timer,
determination is made whether the flow is less than A gpm. If so,
the volumetric flow timer is stopped. If the flow continues to be
greater than A gpm, a determination is made whether the elapsed
time on the volumetric flow timer is a selected elapsed time. The
selected elapsed time in FIG. 3 is B minutes. If the elapsed time
is B minutes, the water is treated and the cycle is repeated.
During the cycle, a determination is made whether a selected time
of the set point timer has elapsed. In FIG. 3, the selected set
point time is C minutes. If C minutes have not elapsed on the set
point timer, the process continues. However, if C minutes have
elapsed, a determination is made with respect to the elapsed time
of the volumetric flow timer at the time that C minutes in the set
point timer have elapsed. The time D of the volumetric flow timer
which has elapsed at the time that C minutes in the set point timer
have elapsed is used for treating the water in proportion to D
divided by B. As an example, if C is 1,440 minutes and B is 1,000
minutes, and if at the time C has occurred the elapsed time D of
volumetric flow timer is 700 minutes, the water will be treated in
proportion to 700 divided by 1,000 or 70 percent of the treatment
that would occur if the volumetric flow timer had timed out prior
to C minutes in the set point timer elapsing. If the fluid
treatment process is used in connection with a water softening
system, the brine valve may be opened for 70 percent of the time
that it would be opened if full recharging were required to deliver
70 percent of the brine solution that would be delivered if full
recharging were delivered.
In FIG. 4, a process is shown that is responsive to demand or time
of day. Referring to FIG. 4, it can be seen that a chronological
timer is set. When the cycle begins, the chronological timer
starts. A determination is made whether it is the proper time of
day to treat the water. If it is the proper time of day to treat
the water, the elapsed time of the volumetric flow timer is
determined and the water is treated in proportion to the elapsed
time D of the volumetric flow timer divided by the selected elapsed
time B of the volumetric flow timer. This process would be used if
one wishes to treat the water, such as by recharging a water
softener, every day at 2:00 a.m.
In FIG. 5, a treatment process is illustrated in which the demand
system is combined with a maximum interval system and also a time
of day system. This mode combines the processes of FIGS. 3 and
4.
In FIG. 6, a flow chart for a treatment process is illustrated in
which a chronological timer is set and after demand has been met,
recharging will not occur until a predetermined time of day. Thus
after the selected elapsed time of B minutes of the volumetric flow
timer has been completed, a determination is made as to whether it
is the proper time of day to treat. Only if both the elapsed time B
has been reached and it is the proper time of day to treat, will
treating commence. Thus, in a softening system, not only must the
volumetric flow timer count the selected time B minutes, but it
must also be the proper time, such as 2:00 a.m., before the
softener is commanded to recharge. This is called demand delayed
recharging.
In accordance with this embodiment of the present invention, the
selected time of B minutes is less than the time required for a
full capacity recharging. For example, assume that a 3,000 gallon
capacity softener should be completely recharged after 1,500
minutes of elapsed time, with the 1,500 minutes of elapsed time
being considered equivalent to 3,000 gallons of water usage. Also
assume that it is desirable to recharge only at the proper time,
such as 2:00 a.m. It has been found to be desirable that the system
is recharged only at a proper time of day, for example, 2:00 a.m.,
and also only if a selected volume of water has been used. In a
system wherein 3,000 gallons of water usage requires capacity
recharging, it may be desirable to recharge after only 1,500
gallons of water usage. However, if there has only been a portion
of water usage, for example, 1,500 gallons instead of the full
3,000 gallons required for capacity recharging, there is no need to
use the same amount of brine for the 1,500 gallon usage that would
be used for the 3,000 gallon usage. Thus, in this embodiment of the
present invention, the system operates to use only the amount of
brine required based upon water usage.
To understand this system, reference is made to FIG. 6. In FIG. 6,
a chronological timer is started and the softener will be recharged
only at the proper time of day, for example, 2:00 a.m. A
determination is made as to whether the flow is greater than A
gallons per minute, wherein A may be two. As long as the flow is
greater than A gallons per minute, the volumetric flow timer will
continue to increment. A determination is made with respect to the
volumetric flow timer as to whether the selected time of B minutes
has elapsed. In this embodiment, B is selected to be less than the
total time that would elapse if the system needed capacity
recharging. For example, if the system needs capacity recharging
once 1,500 minutes has elapsed, then the selected time B may be
equal to 750 minutes. In this manner, the softener will be
recharged if there have been two occurrences: (1) there has been an
elapsed time of 750 minutes, and (2) it is 2:00 a.m.
Now assume that it takes G gallons of water, added to the brine
tank, to make the necessary amount of brine for capacity recharging
of 3,000 gallons of water usage or 1,500 minutes of elapsed time.
If there has been only 750 minutes of water usage at 2:00 a.m.,
there is no need to have used that much brine. In other words,
there is no need to have used G gallons of water. Therefore, in
accordance with this embodiment of the present invention, at
predetermined elapsed time intervals of E minutes, only a fraction
of the total amount of water needed is added to the brine tank. For
example, after each 100 minutes of water usage, only 1/15th of the
capacity amount of water (G) that would normally be added to the
brine system (which is initially dry) will be added. Thus an
elapsed time of E minutes is determined, with E equaling 100, for
example. Every time that E minutes elapse, F gallons of water will
be added to the brine tank. In this example, F may be equal to
1/15th G. Once G gallons of water have been added, the brine is
complete and no further water will be added.
Referring again to FIG. 6, assume that B minutes has elapsed. Thus
750 minutes has elapsed. Assume, however, that it is 9:00 p.m. and
thus it is not yet the proper time of day to recharge. At the time
that B minutes has elapsed, there will have been seven slugs of
water (7 X F) added to the brine tank because every hundred minutes
a slug F of water will be added to the brine tank. Now assume that
between 9:00 p.m. and 2:00 a.m. there is an additional 450 minutes
of elapsed time. This will mean that by the time that 2:00 a.m.
occurs, there has been 1,100 minutes of elapsed time. Since there
has been 1,100 minutes of elapsed time, there have been 11 slugs of
water (11 X F) added to the brine tank. Under no circumstances will
there by more than 15 slugs of water added to the brine tank
because 15 slugs equals G gallons and the system will stop adding
water to the brine tank once G gallons of water have been
added.
FIG. 7 shows a system that is similarin certain respects to the
system of FIG. 6, but in the FIG. 7 system a volumetric flow meter
is used instead of using a volumetric flow timer. Thus a
determination is made as to whether B gallons have flowed. If B
gallons have flowed and it is the proper time of day to recharge,
the softener is recharged. As with FIG. 6, B gallons may be
selected to be only a portion of the total amount of gallons which
would flow to require a full recharging. Like FIG. 6, water is
added to the brine tank in slugs according to predetermined time
intervals of flow. As an example, assume that 3,000 gallons of flow
would require total recharging. Assume further that B is selected
to be 1,500 gallons and 2:00 a.m. is selected as the proper time of
day to recharge. Also assume that E is selected to be 200 gallons.
Each slug of water to be added to the brine tank equals 1/15th of
the total amount of water that would normally be added to the brine
tank (which is initially dry). Thus once the volumetric flow meter
is operating, every time that 200 gallons flow, a slug of water is
added to the brine tank. Once 1,500 gallons of water have flowed
and it is 2:00 a.m., the softener will be recharged. Only the
necessary amount of brine will be used because if at 2:00 a.m.,
2,000 gallons of water have flowed, only 10 slugs of water will
have been added to the brine tank. Likewise, if 2,400 gallons of
water have flowed when 2:00 a.m. occurs, 12 slugs of water will
have been added to the brine tank. On the other hand, if only 1,000
gallons of water have flowed by the time 2:00 a.m. arrives, five
slugs of water will have been added to the brine tank but there
will be no recharging of the softener because the selected volume B
is equal to 1,500 gallons and that amount has not yet flowed. Once
1,500 gallons of water have flowed, however, the softener will be
recharged at the next occurrence of 2:00 a.m.
Another manner of providing brine is to keep the brine chamber full
at all times and to vary the concentration of the brine solution
delivered to the softener as a function of expended capacity. This
is illustrated in FIG. 8. Assume that the softener has a 1,500
minute capacity (C) and that only one-half of that capacity (750
minutes-B) has been used by 2:00 a.m. when the system is scheduled
for regeneration. To this end, a proportioning timer would open the
brine valve just long enough to deliver one-half of the saturated
brine. In other words, a proportioning timer would be used to open
the brine valve for a time that is proportional to the fraction of
the total capacity (C) that has been used. If the full 1,500 minute
capacity has been used by 2:00 a.m., the proportioning timer would
open the brine valve long enough to deliver all of the saturated
brine. On the other hand, if only 60 percent of that capacity has
been used by 2:00 a.m., the proportioning timer would open the
brine valve just 60 percent of the time that it would be open to
deliver the full amount of saturated brine. This embodiment can be
readily understood by referring to FIG. 8 in which the brine valve
is opened in proportion to D over C wherein C is the selected time
of full capacity recharging and D is the actual elapsed time which
may constitute less than the full capacity elapsed time C.
In FIG. 9 a system is shown that operates similarly to the system
of FIG. 8 in that the brine valve is opened in time proportion to
the actual volume of water used as compared with total capacity. In
the FIG. 8 embodiment, however, a volumetric flow meter is used to
determine the actual amount of water that has been used. Thus it
will be assumed that the softener has a capacity of 3,000 gallons
and may be recharged only at 2:00 a.m. if at least 1,500 gallons
have flowed. Using this assumption, B is equal to 1,500 and C is
equal to 3,000. If 2:00 a.m. arrives and only 1,000 gallons have
flowed, there will be no recharging. However, if at 2:00 a.m. the
next morning 1,500 gallons have flowed, the brine valve will be
opened to permit eduction of 1,500/3,000 or 50 percent of the full
amount of brine for capacity and recharging will then occur. If at
2:00 a.m. 2,000 gallons have flowed, then D is equal to 2,000 and
the brine valve will open for two-thirds of the time that it would
normally be open to allow two-thirds of the brine to be educated
for recharging.
It can be seen that a process and system has been provided which
obviate the need for testing the resistance of the bed in order to
determine when recharging is needed. In addition, the process and
system of most embodiments use a timer concept instead of a flow
meter having the problems concomitant with turbine blades and the
present process and system is versatile to allow for demand
regeneration, without delay, demand delayed regeneration and for
providing a reserve brine capacity.
Although illustrative embodiments of the invention have been shown
and described, it is to be understood that various modifications
and substitutions may be made without departing from the novel
spirit and scope of the present invention.
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